Kekuta Manneh's last trip to CenturyLink Field is one he won't soon forget.

The speedy striker scored an electrifying hat trick for the Vancouver Whitecaps in a 4-1 road victory over the Seattle Sounders on Oct. 9, 2013 — a result that briefly kept his team's playoff hopes alive.

With their post-season aspirations again hanging in the balance a year later, the Whitecaps would love nothing more than for Manneh to catch lightning a bottle a second time when they visit their Pacific Northwest rivals on Friday.

"I remember pretty much every single thing about that game," the 19-year-old recalled this week. "It was a great feeling coming out there. (Getting) three points and then being able to score three goals.

"It was fantastic."

As good as Manneh's performance was that night for Vancouver, his 2014 campaign has been equally frustrating for both the player and the club.

The Gambian missed pre-season training because of injury, and after struggling to keep up early in the schedule the Whitecaps put him on a fitness program this summer to build stamina.

Manneh hasn't scored since May 5 and has just three goals from 26 appearances — including 11 starts — but he's shown tremendous jump coming off the bench in recent weeks.

And with attacking options limited thanks to Sebastian Fernandez's suspension for yellow card accumulation and Darren Mattocks being called away on international duty, Manneh looks set to get his chance alongside Erik Hurtado up front against Seattle.

"He's been working hard. That's credit to the kid," said Whitecaps head coach Carl Robinson. "He's shown determination. He's got the bit between his teeth."

But what about a repeat of last season's sublime trip to Seattle that netted his five-foot-nine 145-pound forward international attention and player of the week honours?

Robinson just smiled.

"We'll see. We'll certainly see. I think all signs show me that he's ready," said the Welshman. "If he gets the opportunity to go in on Friday, hopefully he might be exactly the same. I doubt it, but you never know."

Manneh's performances as a substitute helped Vancouver secure two straight wins at home to grab a one-point lead over Portland in the race for the final playoff spot in Major League Soccer's Western Conference, but the Whitecaps enter Friday on the outside looking in after the Timbers downed the San Jose Earthquakes 3-0 on Wednesday. Vancouver has three games left on the schedule, two on the road and one at home, while Portland has two matches remaining on its calendar.

"The belief in this locker-room hasn't teetered or gone anywhere," Whitecaps midfielder Russell Tiebert said prior to the Portland-San Jose result. "I think we all believe in the quality we have. We believe in the players, we believe in each other.

"You can only control what you can. For ourselves, we can only control our result."

Manneh set up the winning goal and had a glorious chance of his own after beating three defenders in the Whitecaps' 2-1 victory over Real Salt Lake on Sept. 27, but it was the performance at the other end of the park a week later in a 2-0 win over FC Dallas that was perhaps even more impressive.

"He was winning headers in our box and his work rate was something people probably don't expect," said Robinson. "We expect it if we're going to be successful as a team and we've been preaching that to him and he showed he takes that information on board."

Robinson said fitness shouldn't be an issue for Manneh, who has been subbed on in five of the last six games, playing a total of 77 minutes.

"He's told me he's got 90 (minutes)," said Robinson. "We'll wait and see on Friday. Obviously the adrenalin as well of the occasion ... if he gets the start then we'll see how long he goes."

Hurtado, who has been a workhorse winning balls and holding up the play for Vancouver, has seen first-hand what Manneh can bring in attack.

Another storyline heading into Friday is the return of Mauro Rosales to Seattle. The veteran midfielder was a fan favourite during his three seasons with the Sounders before getting dealt to Chivas USA in the off-season, who in turn traded the 33-year-old to the Whitecaps in August.

"My main point is to just try to do my best and try to get the three points," Morales said in trying to downplay the occasion. "Our team is working very hard this week to get to the level we need to face this game. We are very confident because we've gotten a few good results.

"We have to push from there and just try to learn from the mistakes we made and keep the good things we've been doing."

Robinson said Rosales has had a huge impact on the pitch — he picked up two assists last weekend — but also away from the games and practices with a young group that is learning how to be professionals.

"He does things correctly," said Robinson. "I've probably seen more of an effect in the locker-room than on the field.

"Make no doubt about it, he's vitally important for us."

Friday's game not only has major implications in the standings for both sides — Seattle has already clinched a playoff spot but is battling the L.A. Galaxy for the best record in the league and the Supporters' Shield — it will also decide the Cascadia Cup, a regional mini-tournament played between the Whitecaps, Sounders and Timbers.

Vancouver won it last season, but Seattle holds a one-point edge so far in 2014 games played amongst the three teams and hasn't taken the title since 2011.

"It's set up to be a fantastic game. Obviously the Cascadia Cup is on the line. They're in the driving position," said Robinson. "They're scoring four goals past each team they play, so we might have to score five to maybe beat them."

One surprise on the Seattle side is that Clint Dempsey wasn't called up to the United States for international duty, meaning the Sounders' best player will be available for the derby-like fixture at what is expected to be a raucous CenturyLink Field

"If you play in England you want to go play at Old Trafford," said Robinson. "If you play in Spain you want to play at Real Madrid. If you play in Germany you want to play at Bayern Munich. We're playing in front of 50,000. Fantastic support, fantastic stadium, fantastic team.

"We'll probably be underdogs — no problem. We'll go in, we'll do our job and we'll see if we can get a win. I've got every confidence in this group."

Notes: Tiebert, fellow Whitecaps midfielder Pedro Morales and defender Jordan Harvey, are each one yellow card away from a one-game suspension. ... With few forward-thinking players available, Robinson said midfielder/striker Kianz Froese will be on the bench Friday. The Cuban-born 18-year-old who grew up in Brunkild, Man., made his professional debut in May against Toronto FC in the first leg of the Amway Canadian Championship semifinal.